haythorn



2 Sheets-Sheet 1 (No Model.) 7

J. HAYTHORN. WATER TUBE BOILER AND TUBE FASTENING. No. 558,685. PatentedApr. 21, 1896.

{No Model.) 2 sheets-sheet 2.

J. HAYTHORN.

' WATER TUBE BOILER AND TUBE FASTENING. No. 558,685. Patented Apr. 21, 1895;

WITNESSES: i lN VE NTOR M ATTORNEYS ATENT FFICE.

JOHN IIAYTHORN, OF GLASGO\V, SCOTLAND.

WATER-TUBE BOILER AND TUBE-FASTENING.

SPECIFICATION forming part of Letters Patent No. 558,685, dated April21, 1896.

' Application filed June 22,1895. Serial No. 553,694.. (No model.)

To all whom it may concern:

Be it known that I, J OHN HAYTHORN, a subject of the Queen of GreatBritain and Ireland, and a resident of Glasgow, Scotland, have inventedcertain Improvements in Water-Tube Boilers and Tube-Eastenings for suchBoilers, of which the following is a specification.

My said invention has for its object to improve the construction ofwater-tube boilers.

A boiler as made with my improvements consists of a number of elementsor sections combined with one or more steam-drums or upper cylinders.Each element consists of a lower narrow horizontal or nearly horizontalbox or casing connected by a number of water-tubes to an upper verticalor nearly vertical box or casing. The elements are placed side by sideand their vertical boxes are connected to a drum or cylinder above them.The set of lower boxes are connected by large pipes to the drum orcylinder for the descent of the water to the lower ends of thewatertubes, or some of the water-tubes may be made larger for thepurpose. Each element may have one or more rows of water-tubesconnecting its upper and lower boxes. hen required for examination orrepair, any one element can be disconnected and taken away withoutdisturbing the neighboring elements. The water-tubes are secured to theboxes or casings by improved externallyapplied fastenings.

I hereunto append two sheets of explana tory drawings, to be hereinafterreferred to, and showing my improvements.

Figure 1 on Sheet 1 of the drawings is an end elevation of onemodification of my improved boiler, one half being shown with thesmoke-box door removed and the other half being in section. Fig. 2 is avertical section of the same as taken at right angles to Fig. 1. Fig. 3on Sheet 2 is a section showing modifications of the improved water-tubefastenmg.

In the drawings the same reference-letters are used to mark the same orlike parts whereever they are repeated.

Each element of the boiler shown in Figs. 1 and 2 consists of a lowernarrow horizontal or nearly horizontal box or casing A, connected by anumber of water-tubes B to an upper Vertical or nearly vertical box orcasin g C. The tubes B, starting vertically from the lower box A, curveover and extend nearly horizontally to the upper box 0, the fireplace Dbeing under the higher nearly horizontal parts of the tubes. Theelements are placed side by side and the upper ends of their uppervertical boxes C are connected by flc nged and bolted joints, or itmight be by screwcouplings, to a box or casing E, extending across theset of elements and connected to a steam drum or cylinder F, which is atright angles to the elements. The box or casing E is divided by apartition G, and the water and steam pass up on the outer side of thepartition into a narrow space formed by the shell of the drum F and aninner shell 11 before entering the interior of the drum, or the .upperends of the vertical boxes 0 may be connected directly to a steam drumor cylinder. The setof lower boxes A may be connected to a box or casing(not shown) lying across their ends and connected by one or more largepipes to the steam drum or cylinder, these connections being for thedescent of the water to the lower ends of the Water-tubes; or, as shownin Figs. 1 and 2, the descent or return downward is provided for whollyor partly through curved tubes L, each connected to the upper and lowerboxes 0 and A. These tubes L are larger than the water-tubes B, and thedescending water enters their upper ends from the space on the innerside of the partition G in the casing E.

The fire-gases acting directly on the nearly horizontal parts of thelower portion of the water-tubes B are, by a partition which may beformed by arranging tubes close together or by inserting firebrick-slabsM, made to extend along the water-tubes from their upper ends towardtheir lower ends, whence they return among the upper portion of thetubes and above the partition M to an uptake N.

Each element may have one or more vertical rows of water-tubes Bconnecting its upper and lower boxes 0 A. WVhen required for examinationor repair, any one element can be disconnected and taken away withoutdisturbing the neighboring elements.

I am enabled to make the upper and lower boxes (3 A, to which thewater-tubes B are fixed, smaller than would otherwise be necessary andwithout plugged or covered openings opposite to the tubes in consequenceof employing an improved fastening which is secured from the outside. Inthe box or casing A, Fig. 3, into which a tube B is to be fixed, asocket is formed with a contracted opening P through its inner end equalto the bore of the tube or a little less. The socket is internallyscrewed to receive an externallyscrewed nut Q, and this nut is screwedinternally to fit a screw-thread formed on the end of the tube 13. Thescrew-thread on the tube is made of finer pitch than that of theinternal screw-thread of the socket. When the nut Q, having been screweda certain distance upon the tube end, is screwed into the socket, itdraws the tube in and forces its end tightly against the contractedinner end of the socket. The end of the tube may bear on a flat surfaceR or a conical surface S at the inner end of the socket, or a washer Tof copper or other suitable material may be interposed to form a tightjoint; or, again, a short tubular piece U may be interposed so that thetube end need not enter the socket, the nut Q, being in such case madelong and strong enough to sufficiently support the tube.

I claim as my invention 1. The improved water-tube boiler consisting ofcombined vertical sections, each comprising a lower approximatelyhorizontal water box, casing, or pipe, connected by curved water-tubesto an approximately vertical casing, box or pipe communicating with asteam drum or cylinder, the connections being made by externally applieddifferential screw-nuts or short tubes, and in combination therewith afurnace under nearly horizontal parts of the water-tubes and a firebrickpartition dividing the water-tubes into lower and upper portions andcausing the fire-gases to pass among the lower portion of water-tubestoward their lower ends and thence among the upper portion of thewatertubes, substantially as herein set forth.

2. The improved water-tube boiler, consisting of combined verticalsections, each comprising a lower approximately horizontal water box,casing or pipe, connected by curved water-tubes to an approximatelyvertical casing, box or pipe communicating with a steam drum orcylinder, and in combination therewith a furnace under nearly horizontalparts of the water-tubes and a firebriek partition dividing thewater-tubes into lower and upper portions and causing the fire-gases topass among the lower portion of water-tubes toward their lower ends andthence among the upper portion of the watertubes, substantially asherein set forth.

The improved fastenings for securing tubes of water-tube boilers tocylinders, pipes, or other parts, and each consisting essentially of anut having two screw-threads of different pitches, one of which threadsscrews upon the tube end and the other in a socket of the cylinder, pipeor other part, the tube end being forced into contact with said socketor piece therein, substantially as set forth.

In testimony whereof I have signed my name to this specification in thepresence of two subscribing witnesses.

JOHN HAYTIIORN. WVitnesses:

EDMOND HUNT, DAVID FERGUSON.

